Cross-scale Modeling of Functional Grading in Musculoskeletal Tissues
type: CreativeWork
description: Interfaces in physiology often present transitional zones with gradual changes in composition, structure, and mechanical properties. For example, the attachment between tendon to bone features a unique interfacial region that is critical for musculoskeletal physiological function. The proposed dissertation aims to identify, through mathematical modeling of graded tissue regions, the ways that these regions contribute to physiological function, and the ways that the degeneration of these regions contribute to pathology. The dissertation introduces new modeling tools for this purpose. By identifying physiological and pathophysiological roles of graded tissue regions, the results in this dissertation serves as a foundation for guiding novel strategies and tissue engineering approaches to repair of graded tissue regions. The dissertation contains three parts. First, we focused on the cross-scale, graded stiffening mechanisms that endow healthy the rotator cuff tendon-to-bone attachment with high resilience. Accumulation of a high volume fraction of mineral inclusions within and upon collagen fibers occurs in a graded fashion as tissue transitions from tendon to bone, but existing homogenization techniques that describe how stiffening emerges hierarchically are not suitable at these high volume fractions of inclusions. We therefore applied homogenization concepts to develop a theoretical method capable of estimating the effective elastic properties of composites containing a high volume fraction of different inclusion types. We applied this method to predict how tissue stiffness varies as a function of mineral volume fraction at the tendon-to-bone attachment, leading to a gradation in mechanical properties that alleviates stress concentrations. Next, we investigated these mechanisms of load transfer to resolve a paradox about the architecture of the rotator cuff, and provide further guidance to repair strategies. The gradation in tissue properties is believed to be centr…
abstract: Interfaces in physiology often present transitional zones with gradual changes in composition, structure, and mechanical properties. For example, the attachment between tendon to bone features a unique interfacial region that is critical for musculoskeletal physiological function. The proposed dissertation aims to identify, through mathematical modeling of graded tissue regions, the ways that these regions contribute to physiological function, and the ways that the degeneration of these regions contribute to pathology. The dissertation introduces new modeling tools for this purpose. By identifying physiological and pathophysiological roles of graded tissue regions, the results in this dissertation serves as a foundation for guiding novel strategies and tissue engineering approaches to repair of graded tissue regions. The dissertation contains three parts. First, we focused on the cross-scale, graded stiffening mechanisms that endow healthy the rotator cuff tendon-to-bone attachment with high resilience. Accumulation of a high volume fraction of mineral inclusions within and upon collagen fibers occurs in a graded fashion as tissue transitions from tendon to bone, but existing homogenization techniques that describe how stiffening emerges hierarchically are not suitable at these high volume fractions of inclusions. We therefore applied homogenization concepts to develop a theoretical method capable of estimating the effective elastic properties of composites containing a high volume fraction of different inclusion types. We applied this method to predict how tissue stiffness varies as a function of mineral volume fraction at the tendon-to-bone attachment, leading to a gradation in mechanical properties that alleviates stress concentrations. Next, we investigated these mechanisms of load transfer to resolve a paradox about the architecture of the rotator cuff, and provide further guidance to repair strategies. The gradation in tissue properties is believed to be centr…
author: Saadat, Fatemeh
language: English (en)
keywords: Mechanical Engineering, Osteopathic Medicine and Osteopathy
date published: 2016-08-15T07:00:00Z
date modified: 2026-07-24T06:13:23Z
provider: Washington University in St. Louis
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Washington University in St. Louis

PropertyValue
property ID: DOI
value: 10.7936/K7862DVQ